In my oppinion thingspeak is a bit more easy and provides a simpler surface to users. After some days, my expreience is feeding cosm a bit difficult than thingspeak...I had problems with updating. I had to take care of library versions under arduino.For cosm you can find Android applications, and they saif they will have sms alerts, but now it is not working.Those who would like to check the feeds on smartphones, have to create own page maybe, because I did not manage to see tha graphs on android phones and Iphone. Thingspeak provides dynamic graphs what can be see on smartphones too ( as I remember for cosm, you have to refresh manually).